Indian Forest Service (Mains), Chemistry optional · 2022 · Paper II
Q7(a). Woodward–Fieser calculations
Question
Calculate the absorption maxima of the two supplied fused-ring structures using Woodward–Fieser rules. [structures given in the paper]
Answer in brief
The conventional estimates are (i) 323 nm for the triene and (ii) 273 nm for the extended five-membered enone.
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CoversWoodward–Fieser rulesλmax calculationUV-visible spectroscopyhomoannular dienecyclopentenone
All parts of Question 7
- 7(a) Woodward–Fieser calculations10 marks
- 7(b) Tautomers and chromophores5 marks
- 7(c) ESR of pyrazine5 marks
- 7(d) Infrared distinctions10 marks
- 7(e) Lead tetraacetate cyclization of butanol10 marks